Allowance For Credit Losses (Activity In The Allowance For Loan Losses) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 83,577	$ 73,476	$ 85,675	$ 56,679
Financing Receivable, Allowance for Credit Loss, Writeoff	1,002	1,529	3,773	6,344
Financing Receivable, Allowance for Credit Loss, Recovery	3,582	1,255	7,060	5,490
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery, Total	(2,580)	274	(3,287)	854
Provision for Loan, Lease, and Other Losses	1,972	13,836	(6,923)	31,213
Ending balance	88,129	87,038	88,129	87,038
Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			6,090
Commercial Financial And Agricultural [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	15,222	23,476	25,608	20,203
Financing Receivable, Allowance for Credit Loss, Writeoff	221	241	675	1,041
Financing Receivable, Allowance for Credit Loss, Recovery	132	181	487	1,061
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery, Total	89	60	188	(20)
Provision for Loan, Lease, and Other Losses	843	3,571	(1,187)	6,764
Ending balance	15,976	26,987	15,976	26,987
Commercial Financial And Agricultural [Member] \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			(8,257)
Commercial Real Estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	22,749	16,469	23,480	10,229
Financing Receivable, Allowance for Credit Loss, Writeoff	0	45	0	45
Financing Receivable, Allowance for Credit Loss, Recovery	428	47	724	690
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery, Total	(428)	(2)	(724)	(645)
Provision for Loan, Lease, and Other Losses	2,991	6,417	(155)	12,014
Ending balance	26,168	22,888	26,168	22,888
Commercial Real Estate [Member] \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			2,119
Construction Real Estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	5,670	6,828	7,288	5,311
Financing Receivable, Allowance for Credit Loss, Writeoff	0	0	0	6
Financing Receivable, Allowance for Credit Loss, Recovery	1,597	35	2,078	628
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery, Total	(1,597)	(35)	(2,078)	(622)
Provision for Loan, Lease, and Other Losses	(1,003)	1,544	(1,204)	2,474
Ending balance	6,264	8,407	6,264	8,407
Construction Real Estate [Member] \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			(1,898)
Residential Real Estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	13,113	10,507	11,363	8,610
Financing Receivable, Allowance for Credit Loss, Writeoff	0	34	37	176
Financing Receivable, Allowance for Credit Loss, Recovery	729	189	859	457
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery, Total	(729)	(155)	(822)	(281)
Provision for Loan, Lease, and Other Losses	(2,080)	546	(3,544)	2,317
Ending balance	11,762	11,208	11,762	11,208
Residential Real Estate [Member] \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			3,121
Consumer [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	26,261	15,624	17,418	12,211
Financing Receivable, Allowance for Credit Loss, Writeoff	781	1,208	3,061	5,060
Financing Receivable, Allowance for Credit Loss, Recovery	696	803	2,912	2,654
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery, Total	85	405	149	2,406
Provision for Loan, Lease, and Other Losses	1,483	1,750	(535)	7,164
Ending balance	27,659	16,969	27,659	16,969
Consumer [Member] \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			10,925
Finance Leases Portfolio Segment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	562	572	518	115
Financing Receivable, Allowance for Credit Loss, Writeoff	0	1	0	16
Financing Receivable, Allowance for Credit Loss, Recovery	0	0	0	0
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery, Total	0	1	0	16
Provision for Loan, Lease, and Other Losses	(262)	8	(298)	480
Ending balance	$ 300	$ 579	300	$ 579
Finance Leases Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			$ 80

Amount, after recovery, of writeoff of financing receivable, charged against allowance for credit loss.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-Section 50
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-Publisher SEC
-Name Regulation S-K (SK)
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-Section 1405
-Paragraph (a)
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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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